Blueberries may
help fight atherosclerosis, also known as hardening of the arteries, according
to results of a preliminary U.S. Department of Agriculture (USDA)-funded study
with laboratory mice. The research provides the first direct evidence that
blueberries can help prevent harmful plaques or lesions, symptomatic of
atherosclerosis, from increasing in size in arteries.
Principal
investigator Xianli Wu, based in Little Rock, Arkansas, with the USDA Agricultural Research Service
(ARS) Arkansas Children’s Nutrition Center and with the University of Arkansas
for Medical Sciences, led the investigation. The findings are reported in the
current issue of the Journal of Nutrition.
Atherosclerosis
is the leading cause of two forms of cardiovascular disease – heart attacks and
strokes. Cardiovascular disease is the No. 1 killer of Americans.
The study compared
the size, or area, of atherosclerotic lesions in 30 young laboratory mice. Half
of the animals were fed diets spiked with freeze-dried blueberry powder for 20
weeks; the diet of the other mice did not contain the berry powder.
Lesion size,
measured at two sites on aorta (arteries leading from the heart), was 39 and 58
percent less than that of lesions in mice whose diet did not contain blueberry
powder.
Earlier studies,
conducted elsewhere, have suggested that eating blueberries may help combat cardiovascular
disease. But direct evidence of that effect has never been presented
previously, Wu says.
The
blueberry-spiked diet contained 1 percent blueberry powder, the equivalent of
about a half-cup of fresh blueberries.
All mice in the
investigation were deficient in apolipoprotein-E, a trait that makes them
highly susceptible to forming atherosclerotic lesions and thus an excellent
model for biomedical and nutrition research.
Wu’s group wants
to determine the mechanism or mechanisms by which blueberries helped control
lesion size. For example, by boosting the activity of four antioxidant enzymes,
blueberries may have reduced the oxidative stress that is a known risk factor
for atherosclerosis.
In follow-up
studies, Wu’s group wants to determine whether eating blueberries in infancy,
childhood and young adulthood would help protect against onset and progression
of atherosclerosis in later years. Early prevention may be especially important
in light of the nation’s epidemic of childhood obesity. Overweight and obesity
increase atherosclerosis risk.
ARS, the USDA’s
principal intramural scientific research agency, operates the Arkansas
Children’s Nutrition Center in conjunction with the University
of Arkansas for Medical Sciences and
the Arkansas Children’s Hospital, all in Little
Rock. The blueberry research is one example of ARS
investigations that are designed to help improve children’s nutrition and
health, a USDA top priority.
